A mobile telecommunications carrier may allocate a significant portion of their annual budget to network planning, troubleshooting, and otherwise improving their network coverage in order to meet the needs of their customers. As a mobile telecommunications carrier expands their network to encompass rural, urban, and other land areas, the ability to determine whether a telecommunications event, such as a voice call or data session, occurred within a building or other indoor area or outdoors becomes increasingly difficult. Mobile telecommunications carriers may utilize predicted service demand, historic traffic usage, and/or demographics for planning network upgrades for areas in which they currently provide mobile telecommunications services, and for planning network expansion into areas in which they intend to provide mobile telecommunications services. These planning metrics, however, are not beneficial for determining the environment in which a telecommunications event occurred.